The aims of the Animal/Pathology Core are to: AIM A. Collect, process, archive and distribute human and animal tissues (Projects 1,2,3,4) AIM B. Perform tumor implantations and illuminations; assist in other treatments of mice (Projects 2,3,4) AIM C. Assist in mouse autopsies (Dr. Durham) and coordinate the movement of animal and human tumor samples for immunohistochemical analysis between Pathology (human or veterinary, as relevant) and the laboratories of Project Leaders. The strength of Core B is that it will provide consistent animal models, animal treatments, tissue collection and pathologic analyses for the projects in this PPG. Given the ?high tech? nature of delivering PDT, this is particularly important. The Core will act as a center point to assure that tissues will be collected and distributed in a consistent manner, based on our SOPS, and this process will be well documented using detailed data collection forms included in the Appendix of Core B. Dr. Sydney Evans will be the director of Core B; Dr. Durham will be responsible for the animal-related immunohistochemistry tasks after autopsy (Aim C). The functions of Core B can be separated into the ANIMAL and the PATHOLOGY subcores. The ANIMAL SUBCORE will be responsible for 1) Aiding the PIs in developing, submitting and maintaining IACUC proposals 2) Ordering animals 3) Performing inter-project animal work, including tumor implantation, illumination, tissue collection The PATHOLOGY SUBCORE will: 1) Aid in the collection, processing, and archiving or storage of animal and human tissues/blood 2) Oversee murine autopsies, collection and submission of tissues for staining/histopathological review